This description relates to processing queries containing a union-type operation.
A query to a data source specifies data to be retrieved from the data source. The query can be provided to the data source (e.g., a database) and a data processing system associated with the data source (e.g., a database management system) can return the data specified by the query. Various techniques can be used to parse the query to identify the data in the data source specified by the query.